Alaska North Slope crude oil production averaged 552,114 barrels per day in August, down 14.9 percent from a July average of 648,539 bpd, a drop primarily attributable to planned shutdowns at Alpine and on the trans-Alaska oil pipeline.

More than half of the decline was due to the annual turnaround at the ConocoPhillips Alaska-operated western North Slope Alpine field. ConocoPhillips spokeswoman Natalie Lowman told Petroleum News in August that the field would be offline for approximately two weeks for planned maintenance, overlapping the trans-Alaska oil pipeline shutdown.

Lowman said in a Sept. 3 e-mail that the critical path for the maintenance was an overhaul of the two main turbines at Alpine. “We also did inspection of two gas train vessels and general maintenance on all the equipment that is normally running,” she said. Since Alpine is a single-train plant, all of the equipment was shut down during the maintenance.

Production was also impacted across the North Slope by the second major maintenance shutdown of the summer of the trans-Alaska oil pipeline by Alyeska Pipeline Service Co.

The Aug. 16-17 shutdown included two major tasks: installation of some 1,700 feet of new 48-inch mainline pipe at Pump Station 2 and replacement of a pig trap value at the Valdez Marine Terminal. Alyeska said on its Web site that the shutdown lasted some 35 hours and that more than 350 employees worked at various locations completing nearly 40 additional work tasks.

See full story in Sept. 7 issue of Petroleum News, available online to subscribers at noon, Sept. 5, at www.PetroleumNews.com